1. Field of the Invention
The present invention relates to a standard wrench or socket wrench with a head capable of rotating laterally with respect to the handle. The handle's rotation allows the wrench to tighten or loosen nuts in locations which are difficult or impossible to reach with a standard wrench.
2. Description of Related Art
Several other inventors have attempted to produce a satisfactory way to allow the head of a wrench to rotate laterally. For example, the invention of William Hetrick Shannon, U.S. Pat. No. 1,265,535, issued on May 7, 1918, uses a ratchet wheel to change the lateral angle of a wrench head. The ratchet is held in place by a handle pressed into a notch on the ratchet wheel by a leaf spring. The wrench is therefore not locked into position unless the handle is grabbed in such a way as to depress the lever.
John H. Burndahl disclosed in U.S. Pat. No. 1,384,887, issued on Jul. 10, 1921, a wrench whose head pivots on a notched wheel. The wheel is held in place by a sliding block, which is held in one of the notches by spring pressure. To rotate the wrench, the block is pushed rearward, the wrench repositioned, and the block released. The Burndahl invention suffers from the disadvantage that, as the notches in the wheel, the sliding block, and the spring experience wear, the notches will enlarge, the block will become smaller, and the spring will weaken. Because the spring tension and close fit between the block and the wheel notches hold the block in the locked position, it is possible that lateral pressure on the wrench could force the block back against the spring, unlocking the wrench. In contrast, the present invention has a locking pin which passes through the ratchet head and the handle on either side of the head; thus wear will only result in some play in the position of the head, not in the head coming unlocked.
U.S. Pat. No. 2,028,561, issued to Emil F. Pilger on Jan. 21, 1936, discloses a rotating-head wrench using a flat spring on the head to engage flutes on the handle to hold the wrench in position. The obvious result is that the spring will eventually weaken, destroying any ability of the head to lock into position.
Stephen A. Gummow disclosed in U.S. Pat. No. 4,406,186, issued on Sep. 27, 1983, a rotating-head socket wrench wherein the end surfaces of the head and handle abut during use, preventing the wrench from moving. To rotate the wrench to a different position, the head slides down the pivot joining the head and handle, taking the two out of contact with each other, and allowing the head to rotate. While this design is very strong, it only allows for three head positions, where the current invention provides for as many positions as there are possible holes drilled in the neck portion of the head ratchet head.
U.S. Pat. No. 4,747,328, issued to Leslie Howard on May 31, 1988, discloses a rotating-head socket wrench wherein the head pivots on a notched wheel, and is held in position by a rod extending through the handle. The rod is held in place by a pair of ball bearings pressed into indentations on the rod by springs. To rotate the head, the user grabs the portion of the rod which sticks out of the handle's end, pulls out, rotates the head, and pushes the rod back into position. As with U.S. Pat. No. 1,384,887 discussed above, wear of the notched wheel could eventually cause the locking rod to pop out of the notch.
James E. Cole disclosed in U.S. Pat. No. 5,419,221 an indexable head ratchet wrench wherein the connection pin between the handle and ratchet head extends through a splined orifice in the handle. The connection includes a slidable member which locks the ratchet head in position when pushed in one direction, and allows the ratchet head to pivot freely in the other position. With the ratchet head unlocked, a nut can be rapidly rotated by moving the handle back and forth.
The February, 1998, Snap-on Hot Tools catalog features a rotating head ratchet wrench that also functions as a speed wrench. The catalog refers to a "spline lock," but does not provide enabling disclosure. One of the tools pictured is stamped, "Patented USA," but no patent number is visible in the picture, and the text does not refer to the patent. Snap-on's product appears to be very similar to the aforementioned Cole patent.
Other patents relating to wrenches include U.S. Pat. No. 2,707,413, issued to Daniel M. Goodnow on May 3, 1955, describing an adjustable open head ratchet wrench; U.S. Pat. No. 5,517,884, issued to Alton W. Sanders on May 21, 1996, describing a speed wrench; U.S. Pat. No. 5,690,006, issued to Doyle H. Pulliam on Nov. 25, 1997, describing a slide-adjustable socket extender for socket wrenches; U.S. Pat. No. 5,570,617, issued to John A. Love on Nov. 5, 1996, describing an extendable extension handle for wrenches, ratchets, tire irons, and other hand tools; French Pat. No. 1,212,685, published on March 25, 1960; and Swiss Pat. No. 133,869, published on Jun. 30, 1929.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.